If I had to put money down I'd say there are two motivations. First it's pure marketing. There are Apple and Microsoft stores in the same shopping center. Amazo

If I had to put money down I'd say there are two motivations. First it's pure marketing. There are Apple and Microsoft stores in the same shopping center. Amazon is promoting its brand. Second, perhaps more far-fetched and to me more interesting, it's a long play by a company famous for long plays. Amazon has predicted a future where they put most brick and mortar bookstores out of business, and recognized this future is not good if you want to sell books.